GB1065357A - Improvements in or related to electrogravitational fluid treatment devices - Google Patents

Abstract

An electrogravitational device comprises a container 10 having sides 11, 12 from which extend at an acute angle ion selective membranes 28, 29, means 34 for introducing fluid to be treated into the container, means 36 for withdrawing the product stream and means 30, 31 for withdrawing fluid from the container from the sides within the acute angles formed by the membranes. In the embodiment shown the ends of the container are formed by membranes 14 and 15 held in place by electrode-compartment-forming plates 16, 17 platinum wire mesh electrodes 18, 19 being placed within the electrode chambers thus formed. <PICT:1065357/C6-C7/1> In operation as shown cation permeable ion selective members are used, with the result that the fluid above the membranes becomes more concentrated and hence more dense than the fluid below the membrane. The dilute layers thus move upwards along the lower surfaces of membranes and thus dilute solution is drawn off via the outlet 36. The more concentrated fluid slides down the upper surface of the membranes and is drawn off via outlets 30 and 31. The container 10 may be formed of rigid plastic tubing containing slots into which the membranes are inserted, and may be provided with an outer jacket which serves to collect the fluid drawn off via the outlets 30, 31. In other embodiments the membranes may incline downwardly; may have parallel to each a plurality of progressively smaller membranes thus forming a group of membranes in each stage Fig. 8 (not shown); or may be formed of one continuous membrane formed into a zig-zag shape, and having holes to permit the flow of fluid there-through. The membranes used may be anion permeable, the positions of cathode and anode then being reversed.